Related papers: CI Aquilae: a recurrent nova with an unusually lon…

We present a spectroscopic monitoring of the transient nova V4745 Sagittarii (Nova Sgr 2003 #1) covering ten months after the discovery. During this period the light curve showed well expressed transient phase in the form of six…

We present the CCD photometry, light curve and time series analysis of the classical nova V2275 Cyg (N Cyg 2001 No.2). The source was observed for 14 nights in total using an R filter in 2002 and 2003 with the 1.5 m Russian-Turkish joint…

From archived and recent high speed photometry of VW Hyi we find Dwarf Nova Oscillations (DNOs) occasionally present throughout outburst, evolving from 14.06 s period at maximum to > 40 s near the end of outburst. A relatively slow increase…

We present near-infrared and optical observations of the nova V496 Scuti 2009 covering various phases - pre-maximum, early decline and nebular - during the first 10 months of its discovery followed by limited observations in early part of…

We present new spectroscopic and photometric observations of ATLAS18qtd/SN 2018cqj, a fast-declining Type Ia supernova with variable H$\alpha$ emission in previously-published nebular phase spectra. ATLAS18qtd is undetected in both…

The second known outburst of the WZ Sge type dwarf nova GW Lib was observed in April 2007. We have obtained unique multiwavelength data of this outburst which lasted ~ 26 days. AAVSO observers recorded the outburst in the optical, which was…

IX Vel has been considered as one of the prototypical novalike cataclysmic variables with thermally stable accretion disks. Using All-Sky Automated Survey (ASAS-3) and All-Sky Automated Survey for Supernovae (ASAS-SN) observations, I found…

GK Persei is an intermediate polar that exhibits a dwarf nova outburst approximately every 1000 days. During previous outbursts the system has displayed kilo-second quasi-periodic oscillations (QPOs) in X-ray emission. These oscillations…

ASASSN-22ak is a transient discovered by the All-Sky Automated Survey for Supernovae and by Gaia in 2022 January. Although this object had been in deep quiescence at least for seven years before this outburst, it has been showing relatively…

We report on the spectral evolution of 6 classical novae, V1186 Sco, V2540 Oph, V4745 Sgr, V5113 Sgr, V458 Vul, and V378 Ser, based on the low-resolution spectra obtained at the Fujii-Bisei Observatory and the Bisei Astronomical…

Nova V2491 Cyg is one of just two detected pre-outburst in X-rays. The light curve of this nova exhibited a rare "re-brightening" which has been attributed by some as the system being a polar, whilst others claim that a magnetic WD is…

The March 2011 outburst of the poorly-studied cataclysmic variable NSV 1436 offered an opportunity to decide between dwarf nova and recurrent nova classifications. We use seven daily observations in the X-ray and UV by the Swift satellite,…

The recurrent nova U Scorpii most recently erupted in 2010. Our collaboration observed the eruption in bands ranging from the Swift XRT and UVOT w2 (193 nm) to K-band (2200 nm), with a few serendipitous observations stretching down to WISE…

The two peculiar Type Ic supernovae (SNe) 1997ef and 1997dq are shown to have very similar photometric and spectral evolution in the epochs when both SNe are observed (i.e. beyond $\sim 80$ days after the explosion). The early light curves…

The photometric and spectroscopic evolution of the He/N and very fast Nova Cyg 2008 N2 (V2491 Cyg) is studied in detail. A primary maximum was reached at V=7.45 +/-0.05 on April 11.37 (+/-0.1) 2008 UT, followed by a smooth decline…

We present high resolution optical echelle spectra and IUE observations during a strong flare on 1993 December 22 in the very active, young, rapidly rotating, single K2 dwarf LQ Hya. The initial impulsive phase of the flare, which started…

The connection between accretion and jet production in accreting white dwarf binary systems, especially dwarf novae, is not well understood. Radio wavelengths provide key insights into the mechanisms responsible for accelerating electrons,…

I observed the very fast nova V838 Her (Nova Her 1991, optical peak at 5-5.4 mag) during the fading phase of the nova eruption in 1991. I detected eclipses, for the first time in the world in any nova during eruption, and the epochs of the…

A classical nova occurs when material accreting onto the surface of a white dwarf in a close binary system ignites in a thermonuclear runaway. Complex structures observed in the ejecta at late stages could result from interactions with the…

We present a newly appreciated FU Ori outburst event that began in 2019 and reached a peak in early 2021. Suspected young stellar object WISE J054452.25+333009.6 experienced substantial brightening, in excess of $-5$ mag at optical…